Contemporary collective action theories put large horizontal digitally connected networks at the center of mass political action. They posit that information sharing among ordinary social media users makes possible new forms of rapid mass political action. However, recent research has shown that influential individuals can play a number of key roles in facilitating networked political action in seemingly leaderless movements. Still, the role of influential individuals in stimulating protest information sharing on social media is an important aspect of networked collective action that remains understudied. This study seeks to address this. Specifically, it investigates the following question: does exposure to appeals to engage in protest increase individuals’ motivation to share protest information? Drawing on evidence from an original survey experiment, this study shows that digital appeals to engage in collective action posted by influential individuals do elicit an increase in motivation to share the appeal. However, this result obtains only for Korean respondents, whereas influential appeals appear to have no effect on Japanese respondents. I argue that this difference is in part a function of different citizenship norms in the two countries, and the corresponding effects on social network dynamics. Preliminary analysis supports this interpretation, but further investigation is warranted.